Question

Answer 1

\(\sqrt{7}-\sqrt{11-4\sqrt{7}}\\ =\sqrt{7}-\sqrt{11-2\sqrt{28}}\\ =\sqrt{7}-\sqrt{7-2\sqrt{4}.\sqrt{7}+4}\\ =\sqrt{7}-\sqrt{\left(\sqrt{7}-\sqrt{4}\right)^2}\\ =\sqrt{7}-\sqrt{7}+\sqrt{4}\\ =2\)

Answer 2

\(\sqrt{7}-\sqrt{11-4\sqrt{7}}\)

\(=\sqrt{7}-\sqrt{7}+2\)

=2